Designers in the fashion world, including Tory Burch, paid tribute. "We are heartbroken and I will miss our dear friend. Rest in Peace, Lee Radziwill," Burch said via Twitter.

Lee Radziwill, the younger sister of Jacqueline Kennedy Onassis, died Friday in New York, according to multiple reports. She was 85.

The socialite and style icon, born Caroline Lee Bouvier, was the mother-in-law of Real Housewives of New York City alum Carole Radziwill, who could not be immediately reached for comment.

Also an actress and interior designer, Radziwill was most successful as a brand ambassador and public relations executive for Giorgio Armani, according to Women's Wear Daily.

Throughout the 1960s and 1970s, Radziwill was a fixture on the New York social scene and famously attended friend Truman Capote's Black and White Ball dressed in a silver and white sparkly column dress, WWD reports.

Designers in the fashion world, including Tory Burch, paid tribute. "We are heartbroken and I will miss our dear friend. Rest in Peace, Lee Radziwill," Burch said via Twitter.

“For me Lee was one of the most elegant women I have ever known, with innate class and intelligence that made her a unique and admirable person,” Massimo Ferragamo, chairman of Salvatore Ferragamo USA, told WWD.

Radziwill was married three times, including to producer, choreographer and director Herbert Ross. She had two children, a son and daughter, according to WWD.

Her sister, former first lady Jacqueline Kennedy, died in 1994 at the age of 64.